Dental brush



A ril 25, 1939. D. R. COLEMAN DENTAL BRUSH Filed Sept. 26, 1956 I II/I/Il/I Ill/II I/ ji a ATTORNEY. v

Patented Apr. 25, 1939 UNITED STATES PATENT OFFICE This invention is a sanitary dental brush comprising a brush stock of rubber having wedge shaped teeth molded integrally therewith and arranged in longitudinal and transverse rows along one side of the stock, to efiiciently clean and polish the teeth and massage the gums.

So called rubber tooth brushes have heretofore been suggested; but have been open to certain objections. For example, they have either been too flabby or too hard to carry out their functions in an efllcient or satisfactory way. I have overcome these objections by making the teeth of wedge shape so that they terminate in relatively fine straight transverse edges and by thus forming these teeth upon a hollow brush stock normally of a relatively small size but possessing such inherent elasticity and resiliency that the stock may be distended by forcing a handle into its hollow confines to place all portions of the stock, as well as the base portions of the several teeth, under considerable stress or tension. When the teeth are stressed in this manner, the base of each tooth is increased in the direction of the length of the brush and is placed under tension which materially stiflens the whole tooth, while tending to hold it in a state of equilibrium. Any pressure against the end of such a tooth may cause the tooth to yield but as soon as the pressure is released it will return to its initial position under its original stress.

Experience with a brush of this kind has shown that it possesses unusual cleaning and massaging properties. It produces a sort of kneading effect which is particularly efilcient for its intended purpose.

An important feature of the invention consists in the use of a handle adapted to normally 40 occupy the interior of the stock to distend the same and which handle is preferably provided with a metal tang which distends the stock for the purposes stated.

Features of the invention, other than those 45 adverted to, will be appment from the hereinafter detailed description and claims, when read in conjunction with the accompanying drawing.

The accompanying drawing illustrates one practical embodiment of the invention, but the 50 construction therein shown is to be understood as illustrative, only, and not as defining the limits of the invention.

Figure 1 is a longitudinal section through a brush embodying the present invention, showing the handle detached.

Figure 2 is a like view, but showing the parts assembled.

Figure 3 shows, in full lines, a top plan view of the brush stock shown in Figure 1 and, in dotted lines, the stock is shown as it is distended 8 after the handle has been associated therewith. The handle is also shown in this figure in dotted lines.

Figure 4 is a section on line 4-4 of Figure 1.,-

Flgure 5 is a section on line 5-5 oi Figure 2; 10.

Figure 6 is a greatly enlarged view of three teeth showing the manner in which these teeth are deformed and stressed when the tang of the handle is introduced into the hollow stock of the brush. 1

The brush of the present invention comprises, generally speaking, a stock I, and a handle 2, the latter of which is provided with a tang 3. The stock is made of resilient, yieldable material, such as vulcanized rubber and is provided 20 on one face with longitudinal and transverse rows of closely spaced apart teeth I. These teeth are molded integral with the stock and are of substantially wedge shape, being tapered from a relatively broad base to a relatively fine trans- 25 verse edge. In their initial molded condition, they are approximately three times as high as the distance across their bases, while the lateral edges of the teeth are parallel. They extend in close succession longitudinally of the stock and 30 are arranged side by side with intervening straight-sided channels 6.

The stock is made hollow to provide therein a cavity 6 having relatively thin walls and into this cavity is adapted to be received.- the tang 85 3 of the handle. The tang is made somewhat longer than the length of the cavity and also of somewhat greater width, but the primary consideration is that it bemade longer than the length of the cavity, the transverse construction being mainly to insure proper gripping between these parts to hold them in predetermined relation after they are assembled.

It is of course possible to make the tang as an integral part of the handle but, as considerable strength is desired in a tang and metal handles are not popular, I preferably make the handle of some composition material and embed one end of a metal tang therein. I have found that aluminum makes a very satisfactory tang. Edi: light, sufiiciently strong and does not cor- After the brush and handle have been independently made, they are assembled by forcing thetallli0fthehalitiielntliiilliiwivlliyi0! the brush stock in such a way that the brush stock is stretched out or elongated sumciently to cover the tang. when this is done, the cross section of the hollow stock is distended and placed under considerable tension, thereby causing the tang to be firmly gripped by the stock in such a way that the stock will not recede longitudinally of the tang, but will be maintained in its distended condition. When the stock is longitudinally distended, however, it will be apparent that the bases of the teeth adjacent the stock must also be distended or broadened out.

This is graphically illustrated in Figure 6, where I have shown three teeth. The full line position shows the teeth as molded, whereas the dotted line positions show the teeth after they have been distended or stressed through longitudinal stretching of the stock. This stretching will occur as indicated by the arrows in this figure and will cause an increase in the length of the base of each tooth, which will place said teeth under a condition of stable equilibrium, so that they may be graphically said to be alive." They appear to be somewhat stifiened by this operation, yet their resiliency appears to be appreciably increased. When drawn across a surface of the gums or the human dentures, they exert a kneading action highly conducive to cleansing of the human dentures and effect a very pleasing and highly eflicient massage of the gums. Their operation is pronouncedly diil'erent from the dead, flabby action of the ordinary rubber bristles or projections heretofore employed in connection with rubber tooth brushes. The teeth of the brush of this invention have a live whip, with sufllcient stiffness to operate properly upon the dentures and gums but not suiliciently stiff to cause any harm thereto.

The rubber teeth, stressed in the manner stated, have an action which simulates the muscular action of the human fingers in giving massage treatment to the gums and this has long been advocated and admittedly gives the most satisfactory results. The present invention has this finger action and is at the same time more sanitary than direct finger application.

The foregoing detailed description sets forth the invention in its preferred practical form, but the invention is to be understood as fully commensurate with the appended claims,

Having thus fully described the invention, what I claim as new and desire to secure by letters Patent is:

1. A dental brush comprising a handle having a tang, in combination with a hollow resilient and flexible stock having a cavity extending longitudinally thereinto from one end thereof to a point adjacent the opposite end of the stock, with longitudinally adjacent rows of juxtaposed wedge shaped teeth integral with one side of the stock, the cavity in said stock being normally of lesser length than the length of the tang and of lesser cross sectional area than the tang and the stock being drawn upon the tang and held in place thereon with the stock in longitudinally stretched condition and with all parts of the interior wall surface of the cavity in contact with the tang, to place the stock and the base portions of the individual teeth under tension in a direction longitudinally of the brush to maintain said teeth in stable equilibrium.

2. A dental brush comprising a handle having a tang, in combination with a hollow resilient and flexible stock having a cavity extending longitudinally thereinto from one end thereof to a point adjacent the opposite end of the stock, with longitudinally adjacent rows of juxtaposed wedge shaped teeth integral with one side of the stock, the cavity in said stock being normally of lesser length than the length of the tang and of lesser cross sectional area than the tang and the stock being drawn upon the tang and held in place thereon with the stock in longitudinally stretched condition, to place the stock and the base portions of the individual teeth under tension in a direction longitudinally of the brush to maintain said teeth in stable equilibrium, the cavity in the stock being completely filled by the tang.

DANIEL R. COLEMAN. 

